NPE with GSS-API + TLS with Active Directory

DirTest.java

	public static void main(String[] args) throws NamingException {
		Hashtable<String, Object> env = new Hashtable<String, Object>();

		env.put(Context.INITIAL_CONTEXT_FACTORY, "com.sun.jndi.ldap.LdapCtxFactory");
		env.put(Context.PROVIDER_URL, "ldaps://<fqdn>");
		env.put(Context.SECURITY_AUTHENTICATION, "GSSAPI");
		env.put(Sasl.SERVER_AUTH, "true");
		env.put(Sasl.QOP, "auth-int");
		env.put("com.sun.jndi.ldap.trace.ber", System.err);
		env.put("java.naming.ldap.version", "3");

		DirContext dirContext = new InitialDirContext(env);
		SearchControls ctls = new SearchControls(SearchControls.OBJECT_SCOPE, 0, 0, args, false, false);

		try {
			NamingEnumeration<SearchResult> search = dirContext.search("", "(objectClass=*)", ctls);
			while (search.hasMore()) {
				SearchResult res = search.next();
				Attributes attrs = res.getAttributes();
				for (String arg : args) {
					Attribute attr = attrs.get(arg);
					if (attr != null) {
						System.out.println(arg + ":");
						NamingEnumeration<?> all = attr.getAll();

						while (all.hasMore()) {
							System.out.println("    " + all.next());
						}
					}
				}
			}
		} catch (LdapReferralException e) {
			e.printStackTrace();
			DirContext dirContext2 = (DirContext) e.getReferralContext();
			System.out.println(dirContext2.getNameInNamespace());
			dirContext2.close();
		}
		dirContext.close();
	}

gistfile1.txt

java -Dsun.security.krb5.debug=true -Djava.security.krb5.conf=C:\Config\Kerberos\krb5.conf
-Djava.security.auth.login.config=C:\Config\Kerberos\login.conf -Djavax.security.auth.useSubjectCredsOnly=false ...